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  <title>Checks if a variable exists in the user cache</title>

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</div><hr /><div id="function.wincache-ucache-exists" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">wincache_ucache_exists</h1>
  <p class="verinfo">(PECL wincache &gt;= 1.1.0)</p><p class="refpurpose"><span class="refname">wincache_ucache_exists</span> &mdash; <span class="dc-title">
   Checks if a variable exists in the user cache
  </span></p>

 </div>
 <div class="refsect1 description" id="refsect1-function.wincache-ucache-exists-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="type">bool</span> <span class="methodname"><strong>wincache_ucache_exists</strong></span>
    ( <span class="methodparam"><span class="type">string</span> <code class="parameter">$key</code></span>
   )</div>

  <p class="para rdfs-comment">
   Checks if a variable with the <em><code class="parameter">key</code></em> exists in the user cache or not.
  </p>
 </div>

 <div class="refsect1 parameters" id="refsect1-function.wincache-ucache-exists-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>

    
     <dt>
<em><code class="parameter">key</code></em></dt>

     <dd>

      <p class="para">
       The <em><code class="parameter">key</code></em> that was used to store the variable in the cache. 
       <em><code class="parameter">key</code></em> is case sensitive.
      </p>
     </dd>

    
   </dl>

  </p>
 </div>

 <div class="refsect1 returnvalues" id="refsect1-function.wincache-ucache-exists-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   Returns <strong><code>TRUE</code></strong> if variable with the <em><code class="parameter">key</code></em> exitsts, 
   otherwise returns <strong><code>FALSE</code></strong>.
  </p>
 </div>

 <div class="refsect1 examples" id="refsect1-function.wincache-ucache-exists-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-551">
    <p><strong>Example #1 Using <span class="function"><strong>wincache_ucache_exists()</strong></span></strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /></span><span style="color: #007700">if&nbsp;(!</span><span style="color: #0000BB">wincache_ucache_exists</span><span style="color: #007700">(</span><span style="color: #DD0000">'green'</span><span style="color: #007700">))<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">wincache_ucache_set</span><span style="color: #007700">(</span><span style="color: #DD0000">'green'</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">wincache_ucache_exists</span><span style="color: #007700">(</span><span style="color: #DD0000">'green'</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
bool(true)
</pre></div>
    </div>    
   </div>
  </p>
 </div>

 <div class="refsect1 seealso" id="refsect1-function.wincache-ucache-exists-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="function"><a href="function.wincache-ucache-set.html" class="function" rel="rdfs-seeAlso">wincache_ucache_set()</a> - Adds a variable in user cache and overwrites a variable if it already exists in the cache</span></li>
    <li class="member"><span class="function"><a href="function.wincache-ucache-add.html" class="function" rel="rdfs-seeAlso">wincache_ucache_add()</a> - Adds a variable in user cache only if variable does not already exist in the cache</span></li>
    <li class="member"><span class="function"><a href="function.wincache-ucache-get.html" class="function" rel="rdfs-seeAlso">wincache_ucache_get()</a> - Gets a variable stored in the user cache</span></li>
    <li class="member"><span class="function"><a href="function.wincache-ucache-clear.html" class="function" rel="rdfs-seeAlso">wincache_ucache_clear()</a> - Deletes entire content of the user cache</span></li>
    <li class="member"><span class="function"><a href="function.wincache-ucache-delete.html" class="function" rel="rdfs-seeAlso">wincache_ucache_delete()</a> - Deletes variables from the user cache</span></li>
    <li class="member"><span class="function"><a href="function.wincache-ucache-meminfo.html" class="function" rel="rdfs-seeAlso">wincache_ucache_meminfo()</a> - Retrieves information about user cache memory usage</span></li>
    <li class="member"><span class="function"><a href="function.wincache-ucache-info.html" class="function" rel="rdfs-seeAlso">wincache_ucache_info()</a> - Retrieves information about data stored in the user cache</span></li>
   </ul>
  </p>
 </div>


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